ThreatSpain: A million almond trees infected by Xylella fastidiosa in Majorca

In the last two decades, the pest Xylella fastidiosa has infected at least one million almond trees in Majorca. Scientist Eduardo Moralejo, who already warned in 2010 of the presence of the bacterium in the island, now confirms that the pest is behind the crop's high mortality, which was initially attributed to the wood-decay fungus. After four months of research, the biologist concluded that around 150,000 trees have been killed by the bacterium over the last decade, while another 800,000 have been infected. This entails that at least 950,000 almond trees have been hit by the disease.

Eduardo Moralejo, who already warned of the Xylella after the first outbreak in Son Carrió in 2010, has been collaborating this summer with the Laboratory of Plant Health of the Government. The main conclusion of the researcher is that the wood-decay fungus that had been identified as causing the death of almond trees is actually an "advanced stage" of the Almond Leaf Scorch Disease (ALSD), the disease caused by the Xylella which has affected almond trees in California. The regional government of the Balearic Islands has also started talking about the disease, after confirming that the Xylella detected coincides genetically with California's strain, which causes the Pierce Disease that has hit vineyards of the island and the United States.

Following this confirmation and after analysing the samples taken at different points of Majorca, the number of infected almond trees is estimated to amount to about one million; 70 percent of the island's total. This summer, the surge in the number of almond trees with symptoms of the pest and the drying of the trees, as revealed by the yellowish colour of the leaves, was perfectly clear. The agricultural sector spoke of "thousands and thousands" and now the researcher Moralejo gives the figure: at least one million infected.